RE: [PATCH v2 tty-next 2/3] 8250: microchip: pci1xxxx: Add rs485 support to quad-uart driver.

[Ilpo Järvinen]

On Tue, 4 Oct 2022, Kumaravel.Thiagarajan@xxxxxxxxxxxxx wrote:

> > -----Original Message-----
> > From: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx>
> > Sent: Monday, October 3, 2022 2:51 PM
> > To: Kumaravel Thiagarajan - I21417 <Kumaravel.Thiagarajan@xxxxxxxxxxxxx>
> > Subject: Re: [PATCH v2 tty-next 2/3] 8250: microchip: pci1xxxx: Add rs485
> > support to quad-uart driver.
> > 
> > On Sat, 1 Oct 2022, Kumaravel Thiagarajan wrote:
> > 
> > > pci1xxxx uart supports rs485 mode of operation in the hardware with
> > > auto-direction control with configurable delay for releasing RTS after
> > > the transmission. This patch adds support for the rs485 mode.
> > >
> > > Signed-off-by: Kumaravel Thiagarajan
> > > <kumaravel.thiagarajan@xxxxxxxxxxxxx>
> > > ---
> > > Changes in v2:
> > > - move pci1xxxx_rs485_config to a separate patch with
> > >   pci1xxxx_rs485_supported.
> > > ---
> > >  drivers/tty/serial/8250/8250_pci1xxxx.c | 57
> > > +++++++++++++++++++++++++
> > >  1 file changed, 57 insertions(+)
> > >
> > > diff --git a/drivers/tty/serial/8250/8250_pci1xxxx.c
> > > b/drivers/tty/serial/8250/8250_pci1xxxx.c
> > > index 41a4b94f52b4..999e5a284266 100644
> > > --- a/drivers/tty/serial/8250/8250_pci1xxxx.c
> > > +++ b/drivers/tty/serial/8250/8250_pci1xxxx.c
> > > +
> > > +             if (rs485->delay_rts_after_send) {
> > > +                     baud_period_in_ns = ((clock_div >> 8) * 16);
> > 
> > Is this 16 perhaps UART_BIT_SAMPLE_CNT?
> Yes. Is there any macro definition for that? I could not find any 
> definition in the above name. 

You're adding it in your 1/3 patch :-).

-- 
 i.